You'll need to begin this recipe a day ahead.
Cassata is one of Sicily's most flamboyant cakes, and its most recognisable. It consists of a sponge, known as pan di Spagna, a sweetened ricotta centre, a coating of marzipan or icing - or more often both - and finally an elaborate, baroque-inspired decoration of glacé fruits and citrus rinds.
This cassata, dating back a thousand years, is different from the popular ice-cream version which is based on similar ingredients and known in Sicily as cassata gelata. The cake was traditionally made in the spring, usually for Easter, when the ricotta, made with spring milk, was at its freshest and sweetest.
The cake's components reflect some of the layers of cultural influences in Sicily's history. The pan di Spagna, as its name suggests, was likely brought to the island by the Spanish. The candying of the citrus rind, according to Antonio Carluccio in his book Italia, was a technique taught to the Sicilians by the Arabs. (Indeed, it was the Arabs who introduced sugar cane to Sicily, which even today is known as the sweets capital of Italy.)
Sicily-based food writer Mary Taylor Simeti says in her book Sicilian Food that the name cassata derives from the Arabic "qas'ah", which is the steep-sided bowl traditionally used to mould the cake. She goes on to write that "the cake, striped with marzipan coloured pale green in memory of the days when one could afford to use pistachio purée, is glazed with white icing, and then crystallised wedges of oranges and pears are placed on top."
Knowing that not everybody's sweet tooth is as sweet as the Sicilians', we've opted to forgo the marzipan layer and have simply tinted the icing pale green. We've assembled the cake without a mould, yet maintained its highly decorative - and flavoursome - appeal.